##建立数据集
y<-c(162,120,223,131,67,167,81,192,116,55,252,232,144,103,212)
x1<-c(274,180,375,205,86,265,98,330,195,53,430,372,236,157,370)
x2<-c(2450,3250,3802,2838,2347,3782,3008,2450,2137,2560,4020,4427,2660,2088,2605)

##建立模型
lm.sol<-lm(y~1+x1+x2)
summary(lm.sol)

##预测
ex<-data.frame(x1=200,x2=3000)
predict(lm.sol,ex,interval="prediction",level=0.95)
